Electric compressor

Abstract

An electric compressor includes: a housing having a stator that has a cylindrical shape; a rotary shaft that is disposed inside the housing and has a rotor facing the stator; a low-pressure stage wheel that is fixed to one side of the rotary shaft in a shaft direction; a high-pressure stage wheel that is fixed to the other side of the rotary shaft in the shaft direction; a motor cooling water passage that is provided on the outside in a radial direction of the stator in the housing; and a wheel side cooling water passage that is provided on at least one of the low-pressure stage side and the high-pressure stage side of the stator in the housing.

1 . An electric compressor comprising:
 a housing having a stator that has a cylindrical shape;   a rotary shaft that is disposed inside the housing and that has a rotor facing the stator;   a low-pressure stage wheel that is fixed to one side of the rotary shaft in a shaft direction;   a high-pressure stage wheel that is fixed to the other side of the rotary shaft in the shaft direction;   a motor cooling water passage that is provided on an outer side in a radial direction of the stator in the housing; and   a wheel side cooling water passage that is provided on at least one of the low-pressure stage side and the high-pressure stage side of the stator in the housing.   
     
     
         2 . The electric compressor according to  claim 1 , wherein
 the motor cooling water passage and the wheel side cooling water passage are connected to each other by a coil side connecting portion extending along a shaft direction of the stator.   
     
     
         3 . The electric compressor according to  claim 2 , wherein
 the wheel side cooling water passage is provided discontinuously along a circumferential direction of the stator, one end side of the wheel side cooling water passage in the circumferential direction is connected to the coil side connecting portion, and the other end side of the wheel side cooling water passage in the circumferential direction is connected to a cooling water inlet portion or a cooling water outlet portion.   
     
     
         4 . The electric compressor according to  claim 3 , wherein
 the cooling water inlet portion is provided in any one of the motor cooling water passage and the wheel side cooling water passage, and the cooling water outlet portion is provided in the other of the motor cooling water passage and the wheel side cooling water passage.   
     
     
         5 . The electric compressor according to  claim 1 , wherein
 the wheel side cooling water passage includes a low-pressure stage side cooling water passage provided on the low-pressure stage side of the stator in the housing, and a high-pressure stage side cooling water passage provided on the high-pressure stage side of the stator.   
     
     
         6 . The electric compressor according to  claim 1 , wherein
 the motor cooling water passage has a low-pressure stage side motor cooling water passage and a high-pressure stage side motor cooling water passage that are provided at intervals in a shaft direction of the stator, and the low-pressure stage side motor cooling water passage and the high-pressure stage side motor cooling water passage are discontinuous in a circumferential direction of the stator and communicate with each other via a motor side connecting portion.   
     
     
         7 . The electric compressor according to  claim 5 , wherein
 the motor cooling water passage has a low-pressure stage side motor cooling water passage and a high-pressure stage side motor cooling water passage that are provided at intervals in a shaft direction of the stator, the low-pressure stage side motor cooling water passage and the high-pressure stage side motor cooling water passage are discontinuous in a circumferential direction of the stator and communicate with each other via a motor side connecting portion, the low-pressure stage side motor cooling water passage is connected to the low-pressure stage side cooling water passage by a low-pressure coil side connecting portion, and the high-pressure stage side motor cooling water passage is connected to the high-pressure stage side cooling water passage by a high-pressure coil side connecting portion.   
     
     
         8 . The electric compressor according to  claim 1 , wherein
 a passage area of the wheel side cooling water passage varies in a flow circumferential direction of the cooling water.   
     
     
         9 . The electric compressor according to  claim 1 , wherein
 the wheel side cooling water passage continuously bends in the radial direction of the stator in a flow circumferential direction of the cooling water.   
     
     
         10 . The electric compressor according to  claim 1 , wherein
 the motor cooling water passage and the wheel side cooling water passage are set in a range of 10 μm to 100 μm in surface roughness Ra of an inner peripheral surface.   
     
     
         11 . The electric compressor according to  claim 1 , further comprising:
 an air passage that supplies cooling air to at least the stator, wherein   the wheel side cooling water passage cools an air bearing that rotatably supports the rotary shaft with respect to the housing.   
     
     
         12 . The electric compressor according to  claim 2 , wherein
 the wheel side cooling water passage includes a low-pressure stage side cooling water passage provided on the low-pressure stage side of the stator in the housing, and a high-pressure stage side cooling water passage provided on the high-pressure stage side of the stator.   
     
     
         13 . The electric compressor according to  claim 3 , wherein
 the wheel side cooling water passage includes a low-pressure stage side cooling water passage provided on the low-pressure stage side of the stator in the housing, and a high-pressure stage side cooling water passage provided on the high-pressure stage side of the stator.   
     
     
         14 . The electric compressor according to  claim 4 , wherein
 the wheel side cooling water passage includes a low-pressure stage side cooling water passage provided on the low-pressure stage side of the stator in the housing, and a high-pressure stage side cooling water passage provided on the high-pressure stage side of the stator.   
     
     
         15 . The electric compressor according to  claim 2 , wherein
 the motor cooling water passage has a low-pressure stage side motor cooling water passage and a high-pressure stage side motor cooling water passage that are provided at intervals in a shaft direction of the stator, and the low-pressure stage side motor cooling water passage and the high-pressure stage side motor cooling water passage are discontinuous in a circumferential direction of the stator and communicate with each other via a motor side connecting portion.   
     
     
         16 . The electric compressor according to  claim 3 , wherein
 the motor cooling water passage has a low-pressure stage side motor cooling water passage and a high-pressure stage side motor cooling water passage that are provided at intervals in a shaft direction of the stator, and the low-pressure stage side motor cooling water passage and the high-pressure stage side motor cooling water passage are discontinuous in a circumferential direction of the stator and communicate with each other via a motor side connecting portion.   
     
     
         17 . The electric compressor according to  claim 4 , wherein
 the motor cooling water passage has a low-pressure stage side motor cooling water passage and a high-pressure stage side motor cooling water passage that are provided at intervals in a shaft direction of the stator, and the low-pressure stage side motor cooling water passage and the high-pressure stage side motor cooling water passage are discontinuous in a circumferential direction of the stator and communicate with each other via a motor side connecting portion.   
     
     
         18 . The electric compressor according to  claim 5 , wherein
 the motor cooling water passage has a low-pressure stage side motor cooling water passage and a high-pressure stage side motor cooling water passage that are provided at intervals in a shaft direction of the stator, and the low-pressure stage side motor cooling water passage and the high-pressure stage side motor cooling water passage are discontinuous in a circumferential direction of the stator and communicate with each other via a motor side connecting portion.   
     
     
         19 . The electric compressor according to  claim 2 , wherein
 a passage area of the wheel side cooling water passage varies in a flow circumferential direction of the cooling water.   
     
     
         20 . The electric compressor according to  claim 3 , wherein
 a passage area of the wheel side cooling water passage varies in a flow circumferential direction of the cooling water.